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Home >> Ford >> 1991 >> Bronco 4.9 Y, Standard, M5OD-R2 >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - System/Component Tests >> EDIS System (4.0L AEROSTAR, Explorer, NAVAJO & Ranger) >> Pinpoint Test D

Pinpoint Test D

  1. Check For VBAT Open To Coil  With ignition off and ECA connected, install EDIS diagnostic cable to BOB, EDIS module, and coil pack. Do not connect VR sensor tee. Use EDIS "6" overlay (if available). Connect EDIS diagnostic cable negative lead to battery. Set EDIS diagnostic cable box switch to "4/6 cylinder" position. Set DVOM on 20-volt DC scale. With KOEO, measure voltage between VBATC (5) and BAT (7) at BOB. If DC voltage is 10.5 volts or more, go to step 2). If voltage is less than 10.5, repair open VBAT to EDIS module circuit. Remove test equipment and reconnect all components. Clear Continuous Memory Codes and rerun Quick Test.
  2. Verify Vehicle Operating Mode  If vehicle will crank and start, go to step 4). If vehicle will not crank and start, go to step 3).
  3. Check C1, C2, C3 In Sequence At Coil Pack During Cranking  With ignition off and ECA connected, set DVOM on 20-volt AC scale, crank engine and measure voltage between BAT (7) and each coil C1C (3), C2C (6), C3C (10) at BOB. If stabilized AC voltage reading is less than .2 volt, replace coil pack. Remove all test equipment and reconnect all components. Clear Continuous Memory Codes and rerun Quick Test. If voltage is .2 volt or more, go to step 5).
  4. Check C1, C2, C3 In Sequence At Coil Pack With Engine Running  With ignition off and ECA connected, set DVOM on 20-volt AC scale, crank engine and measure voltage between BAT (7) and each coil C1C (3), C2C (6), C3C (10) at BOB. If stabilized AC voltage reading is less than 1.0 volt, replace coil pack. Remove all test equipment, and reconnect all components. Clear Continuous Memory Codes, and rerun Quick Test. If voltage is 1.0 volt or more, go to step 5).
  5. Check C1, C2, C3 In Sequence At Coil Pack  KOEO Coil Fault With ignition off and ECA disconnected, set DVOM on 20-volt DC scale. With KOEO, measure voltage between BAT (7) and each coil C1C (3), C2C (6), C3C (10) at BOB. If each DC voltage reading is 10.5 volts or more, go to step 6). If voltage is less than 10.5 volts, go to step 10).
  6. Check C1, C2, C3 In Sequence At EDIS Module  KOEO Coil Fault - With ignition off and ECA disconnected, set DVOM on 20-volt DC scale. With KOEO, measure voltage between BAT (7) and each coil C1E (53), C2E (55), C3E (54) at BOB. If each DC voltage reading is 10.5 volts or more, go to step 7). If voltage is less than 10.5 volts, repair open circuit. Remove all test equipment and reconnect all components. Clear Continuous Memory Codes and rerun Quick Test.
  7. Check C1, C2, C3 In Sequence At Coil Pack  Isolate Coil With ignition off and ECA disconnected, disconnect coil pack from coil tee. Leave EDIS diagnostic cable connected to vehicle harness connector. Set DVOM on 20-volt DC scale. With KOEO, measure voltage between BAT (7) and each coil C1C (3), C2C (6), C3C (10) at BOB. If each DC voltage reading is less than .5 volt, go to step 9). If voltage is .5 volt or more, go to step 8).
  8. Check C1, C2, C3 In Sequence At Coil Pack  Isolate EDIS Module With ignition off and ECA disconnected, disconnect EDIS module from EDIS module tee. Leave EDIS diagnostic cable connected to vehicle harness connector. Set DVOM on 20-volt DC scale. With KOEO, measure voltage between BAT (7) and each coil C1C (3), C2C (6), C3C (10) at BOB. If each DC voltage reading is less than .5 volt, replace EDIS module. Remove all test equipment and reconnect all components. Clear Continuous Memory Codes and rerun Quick Test. If voltage is .5 volt or more, repair short circuit. Remove all test equipment and reconnect all components. Clear Continuous Memory Codes and rerun Quick Test.
  9. Check C1, C2, C3 Coil Primary  With ignition off and ECA disconnected, reconnect coil pack to coil tee. Set DVOM on 20-ohm scale. Measure resistance between VBATC (5) and each coil C1C (3), C2C (6), C3C (10) at BOB. If each resistance reading is .8 ohms or more, replace EDIS module. Remove all test equipment and reconnect all components. Clear Continuous Memory Codes and rerun Quick Test. If resistance reading less than .8 ohm, replace coil pack. Remove all test equipment and reconnect all components. Clear Continuous Memory Codes and rerun Quick Test.
  10. Check C1, C2, C3 Short To Ground In Coil Pack  With ignition off and ECA disconnected, set DVOM on 2-k/ohm scale. Measure resistance between BAT (7) and each coil C1C (3), C2C (6), C3C (10) at BOB. If each resistance reading is less than 1200 ohms, go to step 11). If resistance reading is 1200 ohms or more, replace coil pack. Remove all test equipment, and reconnect all components. Clear Continuous Memory Codes, and rerun Quick Test.
  11. Check C1, C2, C3 Short To Ground In Harness  With ignition off and ECA disconnected, disconnect EDIS coil tee from coil pack and vehicle harness connector. Disconnect EDIS module from EDIS module tee, leaving EDIS cable connected to vehicle harness connector. Set DVOM on 2-k/ohm scale. Measure resistance between BAT (7) and each coil C1C (3), C2C (6), C3C (10) at BOB. If any resistance reading is less than 5 ohms, repair short. Remove all test equipment, and reconnect all components. Clear Continuous Memory Codes, and rerun Quick Test. If any resistance reading is 5 ohms or more, replace EDIS module. Remove all test equipment, and reconnect all components. Clear Continuous Memory Codes, and rerun Quick Test.
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